diff options
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/Locking | 10 | ||||
| -rw-r--r-- | Documentation/filesystems/nilfs2.txt | 1 | ||||
| -rw-r--r-- | Documentation/filesystems/porting | 28 | ||||
| -rw-r--r-- | Documentation/filesystems/ubifs.txt | 28 | ||||
| -rw-r--r-- | Documentation/filesystems/vfs.txt | 30 |
5 files changed, 55 insertions, 42 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 57d827d6..7e46991 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -52,7 +52,7 @@ ata *); void (*put_link) (struct dentry *, struct nameidata *, void *); void (*truncate) (struct inode *); int (*permission) (struct inode *, int, unsigned int); - int (*check_acl)(struct inode *, int, unsigned int); + int (*get_acl)(struct inode *, int); int (*setattr) (struct dentry *, struct iattr *); int (*getattr) (struct vfsmount *, struct dentry *, struct kstat *); int (*setxattr) (struct dentry *, const char *,const void *,size_t,int); @@ -80,7 +80,7 @@ put_link: no truncate: yes (see below) setattr: yes permission: no (may not block if called in rcu-walk mode) -check_acl: no +get_acl: no getattr: no setxattr: yes getxattr: no @@ -412,7 +412,7 @@ prototypes: int (*open) (struct inode *, struct file *); int (*flush) (struct file *); int (*release) (struct inode *, struct file *); - int (*fsync) (struct file *, int datasync); + int (*fsync) (struct file *, loff_t start, loff_t end, int datasync); int (*aio_fsync) (struct kiocb *, int datasync); int (*fasync) (int, struct file *, int); int (*lock) (struct file *, int, struct file_lock *); @@ -438,9 +438,7 @@ prototypes: locking rules: All may block except for ->setlease. - No VFS locks held on entry except for ->fsync and ->setlease. - -->fsync() has i_mutex on inode. + No VFS locks held on entry except for ->setlease. ->setlease has the file_list_lock held and must not sleep. diff --git a/Documentation/filesystems/nilfs2.txt b/Documentation/filesystems/nilfs2.txt index d5c0cef..873a2ab 100644 --- a/Documentation/filesystems/nilfs2.txt +++ b/Documentation/filesystems/nilfs2.txt @@ -40,7 +40,6 @@ Features which NILFS2 does not support yet: - POSIX ACLs - quotas - fsck - - resize - defragmentation Mount options diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 6e29954..b4a3d76 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -400,10 +400,32 @@ a file off. -- [mandatory] - --- -[mandatory] ->get_sb() is gone. Switch to use of ->mount(). Typically it's just a matter of switching from calling get_sb_... to mount_... and changing the function type. If you were doing it manually, just switch from setting ->mnt_root to some pointer to returning that pointer. On errors return ERR_PTR(...). + +-- +[mandatory] + ->permission() and generic_permission()have lost flags +argument; instead of passing IPERM_FLAG_RCU we add MAY_NOT_BLOCK into mask. + generic_permission() has also lost the check_acl argument; ACL checking +has been taken to VFS and filesystems need to provide a non-NULL ->i_op->get_acl +to read an ACL from disk. + +-- +[mandatory] + If you implement your own ->llseek() you must handle SEEK_HOLE and +SEEK_DATA. You can hanle this by returning -EINVAL, but it would be nicer to +support it in some way. The generic handler assumes that the entire file is +data and there is a virtual hole at the end of the file. So if the provided +offset is less than i_size and SEEK_DATA is specified, return the same offset. +If the above is true for the offset and you are given SEEK_HOLE, return the end +of the file. If the offset is i_size or greater return -ENXIO in either case. + +[mandatory] + If you have your own ->fsync() you must make sure to call +filemap_write_and_wait_range() so that all dirty pages are synced out properly. +You must also keep in mind that ->fsync() is not called with i_mutex held +anymore, so if you require i_mutex locking you must make sure to take it and +release it yourself. diff --git a/Documentation/filesystems/ubifs.txt b/Documentation/filesystems/ubifs.txt index 8e4fab6..a0a61d2 100644 --- a/Documentation/filesystems/ubifs.txt +++ b/Documentation/filesystems/ubifs.txt @@ -111,34 +111,6 @@ The following is an example of the kernel boot arguments to attach mtd0 to UBI and mount volume "rootfs": ubi.mtd=0 root=ubi0:rootfs rootfstype=ubifs - -Module Parameters for Debugging -=============================== - -When UBIFS has been compiled with debugging enabled, there are 2 module -parameters that are available to control aspects of testing and debugging. - -debug_chks Selects extra checks that UBIFS can do while running: - - Check Flag value - - General checks 1 - Check Tree Node Cache (TNC) 2 - Check indexing tree size 4 - Check orphan area 8 - Check old indexing tree 16 - Check LEB properties (lprops) 32 - Check leaf nodes and inodes 64 - -debug_tsts Selects a mode of testing, as follows: - - Test mode Flag value - - Failure mode for recovery testing 4 - -For example, set debug_chks to 3 to enable general and TNC checks. - - References ========== diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index 88b9f55..52d8fb8 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -229,6 +229,8 @@ struct super_operations { ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t); ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t); + int (*nr_cached_objects)(struct super_block *); + void (*free_cached_objects)(struct super_block *, int); }; All methods are called without any locks being held, unless otherwise @@ -301,6 +303,26 @@ or bottom half). quota_write: called by the VFS to write to filesystem quota file. + nr_cached_objects: called by the sb cache shrinking function for the + filesystem to return the number of freeable cached objects it contains. + Optional. + + free_cache_objects: called by the sb cache shrinking function for the + filesystem to scan the number of objects indicated to try to free them. + Optional, but any filesystem implementing this method needs to also + implement ->nr_cached_objects for it to be called correctly. + + We can't do anything with any errors that the filesystem might + encountered, hence the void return type. This will never be called if + the VM is trying to reclaim under GFP_NOFS conditions, hence this + method does not need to handle that situation itself. + + Implementations must include conditional reschedule calls inside any + scanning loop that is done. This allows the VFS to determine + appropriate scan batch sizes without having to worry about whether + implementations will cause holdoff problems due to large scan batch + sizes. + Whoever sets up the inode is responsible for filling in the "i_op" field. This is a pointer to a "struct inode_operations" which describes the methods that can be performed on individual inodes. @@ -333,8 +355,8 @@ struct inode_operations { void * (*follow_link) (struct dentry *, struct nameidata *); void (*put_link) (struct dentry *, struct nameidata *, void *); void (*truncate) (struct inode *); - int (*permission) (struct inode *, int, unsigned int); - int (*check_acl)(struct inode *, int, unsigned int); + int (*permission) (struct inode *, int); + int (*get_acl)(struct inode *, int); int (*setattr) (struct dentry *, struct iattr *); int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *); int (*setxattr) (struct dentry *, const char *,const void *,size_t,int); @@ -423,7 +445,7 @@ otherwise noted. permission: called by the VFS to check for access rights on a POSIX-like filesystem. - May be called in rcu-walk mode (flags & IPERM_FLAG_RCU). If in rcu-walk + May be called in rcu-walk mode (mask & MAY_NOT_BLOCK). If in rcu-walk mode, the filesystem must check the permission without blocking or storing to the inode. @@ -755,7 +777,7 @@ struct file_operations { int (*open) (struct inode *, struct file *); int (*flush) (struct file *); int (*release) (struct inode *, struct file *); - int (*fsync) (struct file *, int datasync); + int (*fsync) (struct file *, loff_t, loff_t, int datasync); int (*aio_fsync) (struct kiocb *, int datasync); int (*fasync) (int, struct file *, int); int (*lock) (struct file *, int, struct file_lock *); |
